We could supply all our energy needs without altering the global climate.

Is there not enough wind blowing across the planet to satiate our demands for electricity? If there is, would harnessing that much of it begin to actually affect the climate?

Two studies published this week tried to answer these questions. Long story short: we could supply all our power needs for the foreseeable future from wind, all without affecting the climate in a significant way.

The first study, published in this week’s Nature Climate Change, was performed by Kate Marvel of Lawrence Livermore National Laboratory with Ben Kravitz and Ken Caldeira of the Carnegie Institution for Science. Their goal was to determine a maximum geophysical limit to wind power—in other words, if we extracted all the kinetic energy from wind all over the world, how much power could we generate?

In order to calculate this power limit, the team used the Community Atmosphere Model (CAM), developed by National Center for Atmospheric Research. Turbines were represented as drag forces removing momentum from the atmosphere, and the wind power was calculated as the rate of kinetic energy transferred from the wind to these momentum sinks. By increasing the drag forces, a power limit was reached where no more energy could be extracted from the wind.

The authors found that at least 400 terawatts could be extracted by ground-based turbines—represented by drag forces on the ground—and 1,800 terawatts by high-altitude turbines—represented by drag forces throughout the atmosphere. For some perspective, the current global power demand is around 18 terawatts.

The second study, published in the Proceedings of the National Academy of Sciences by Mark Jacobsen at Stanford and Cristina Archer at the University of Delaware, asked some more practical questions about the limits of wind power. For example, rather than some theoretical physical limit, what is the maximum amount of power that could actually be extracted by real turbines?

For one thing, turbines can’t extract all the kinetic energy from wind—no matter the design, 59.3 percent, the Betz limit, is the absolute maximum. Less-than-perfect efficiencies based on the specific turbine design reduce the extracted power further.

Another important consideration is that, for a given area, you can only add so many turbines before hitting a limit on power extraction—the area is "saturated," and any power increase you get by adding any turbines ends up matched by a drop in power from existing ones. This happens because the wakes from turbines near each other interact and reduce the ambient wind speed. Jacobsen and Archer expanded this concept to a global level, calculating the saturation wind power potential for both the entire globe and all land except Antarctica.

Like the first study, this one considered both surface turbines and high-altitude turbines located in the jet stream. Unlike the model used in the first study, though, these were placed at specific altitudes: 100 meters, the hub height of most modern turbines, and 10 kilometers. The authors argue improper placement will lead to incorrect reductions in wind speed.

Jacobsen and Archer found that, with turbines placed all over the planet, including the oceans, wind power saturates at about 250 terawatts, corresponding to nearly three thousand terawatts of installed capacity. If turbines are just placed on land and shallow offshore locations, the saturation point is 80 terawatts for 1,500 terawatts of installed power.

For turbines at the jet-stream height, they calculated a maximum power of nearly 400 terawatts—about 150 percent of that at 100 meters.

These results show that, even at the saturation point, we could extract enough wind power to supply global demands many times over. Unfortunately, the numbers of turbines required aren’t plausible—300 million five-megawatt turbines in the smallest case (land plus shallow offshore).

What about the impacts of too many wind turbines on the climate? Both studies addressed this issue. The first study found that, as you might expect, if we extract wind power at the geophysical limit—removing all of the available kinetic energy from the wind—there are significant impacts on the climate. With only ground turbines, the average global temperature would increase by a few degrees Celsius, while high-altitude turbines would lead to a global cooling of more than ten degrees.

At the much more reasonable power levels of simply meeting global demands, both studies reported minimal environmental impacts. Local temperatures could change around 0.1 degrees Celsius, while local precipitation could be affected by about 1 percent.

Of course, knowing that there is enough wind energy to supply all our needs doesn’t necessarily mean we are going to harness it. Economic and political hurdles will have to be overcome, but knowing that the environmental impact would be minimal should reassure some critics.

Promoted Comments

Didn't realise there were any climate implications of wind turbines; that's interesting.

Could someone please enlighten me though as to why there's two quoted numbers, like the 250 terwatts vs 3000 terwatts? Tad confused..

" Jacobsen and Archer found that, with turbines placed all over the planet, including the oceans, wind power saturates at about 250 terawatts, corresponding to nearly three thousand terawatts of installed capacity. If turbines are just placed on land and shallow offshore locations, the saturation point is 80 terawatts for 1,500 installed terawatts of installed power. "

Wind turbines are rated in terms of the amount of power they could produce if the wind was blowing at the maximum speed they're able to handle; that's the 1500/3000TW number. But since the wind rarely blows at that level and power extracted is a function of windspeed cubed the average power produced is much lower, that's the 80/250TW number.

the saturation point is 80 terawatts for 1,500 installed terawatts of installed power.

Kyle can you delete one of these "installed"s?

Also, you should explain that those 10km-high wind turbines are a flying kite style wind turbine that is on the drawing board.

Obviously some people in the forum don't understand the value of this study. First, in the past some (crazy) people worried that all the wind turbines we are installing could cause climate change. They do cause local wind speed reduction (duh) and some local temperature increase. So does this imply a global climate effect? So these new studies ask a few questions: What's the most energy we could possibly get out of the global winds with maximum possible installation of wind turbines. They DID NOT imply that we should/could/will do this. They calculated how much power we could possibly get out of the global winds, and then determined that there WOULD be a significant climate effect IF we extracted the MAXIMUM POSSIBLE power from the wind. They also noted that the MAXIMUM POSSIBLE power we could get out of the wind is MANY TIMES MORE than today's total global electrical demand.

Then they moved to the next scenario. What if ALL of the world's CURRENT ELECTRIC DEMAND were supplied by wind turbines? They found that that amount of power extraction from the wind WOULD NOT cause a significant global climate effect.

172 Reader Comments

IMHO large scale wind power is great in theory -but a nightmare in practice.

The logistical, manpower, maintenance and cost requirements involved in keeping a large wind farm going are massive. Especially after the equipment has been working for a few years.

(Which is why, for instance, most of the turbines at the wind farm on the south side of of the big island of Hawaii are not functioning. The costs became prohibitive.)

In case you're wondering, the company that built them (if it is who I think it is) went belly up recently and hadn't been able to pay their bills for a while now. Many companies that they bought parts and services from had black-listed them because of their failure to pay up. They ended up selling to the highest bidder to try and pay off their debts. No idea what's going to happen to those towers now.

What about the birds!? They forgot the environmental impact of killing off all birds in their model.

We'll call it a government subsidy for KFC franchises so they can lower the prices of their "chicken.". Seriously, have you seen their prices lately? WTH happened there? KFC used to be a cheap place to eat! Now it's something like $20 for an 8-piece bucket.

There is no real concept of 'storing power'. That's not how the grid works, either you use it, or auction it off for someone else to use. So what happens at night? Or when there is no wind?

I'm not nitpicking but instead trying to add something to the conversation as I'm somewhat familiar with the power industry. In some geographical locations you can indeed 'store power'. One that readily comes to mind is Raccoon Mountain Pumped Storage Facility in Tennessee. During off peak hours when generation outstrips demand, TVA (Tennessee Valley Authority) pumps large amounts of water to a man made lake on the top of the mountain creating a vast resource of potential energy. During peak hours the pumps (turbines in this case) reverse and act as generators, recapturing the energy kinetically just as a hydroelectric dam does. It's a pretty neat concept and works well.

But you are not really storing power, you are using a bunch of power that you cannot use (based on the grid concepts above) to store potential power. Now of course there is really no difference between two in terms of the final product, but its not scalable to other power solutions and certainly not part of the grid itself.

Power stations of any variety could potentially store excess power too, but at what cost? Chances are that a)we don't have the technology to do so in such high volumes, and b)it would not be feasible even if we did.

As Dubya Bush explained in a State of the Union speech, excess electricity can be stored as hydrogen, wuich can be mixed with natural gas. Because it is excess electrcity, the hydrogen would be chea extra revenue. But Obama does not want to do that because he s catering to foreign despots. Witness the current attacks on our embassies.

We are all remembering, of course, that anyone with half a brain realizes that you don't put all your eggs in one basket, or generate all your power from one source. Right?

Until the someday promise of clean fusion power comes true, and we are still centuries from that, we need multiple sources of power. Wind power, combined with hydro, solar, geo, and nuclear, are good moves to help us rely less on non-replacable resources like coal, oil and nat gas. That way we can make those finite resources last as long as possible and use them for more emergency, immediate need, types of situations.

Doing research into just how far we can feasibly go with wind power helps planners decide how much of each of the above should be budgeted for.

Fusion will always be radioactive. That is what it is about. Wind will always be expensive because while air flows fast, it is sporadic and light. Wwter is 865 times heavier so you can get a lot of useable horsepower.

How cute. Start thinking for yourself and try to understand the enormous scales of it all.directly.<snip>

<snip>As an aside, "how cute"? It's not necessary to be a dick, reel it back in.

To be honest your quote of "That's lovely math, but it's meaningless without comparison." earlier was pretty dismissive, kinda pissed me off, but I let it go. I think what you have above is a merely a reflection of the tone you took in your earlier post. I'd call it well played.

I am sorry you read it that way, but it's true, isn't it? The numbers only have any meaning when compared to the cost of your other options. One way or another, we must have electricity.

What about the birds!? They forgot the environmental impact of killing off all birds in their model.

Meh, house cats currently kill like 100x more birds than windmills ever dreamed of by most counts I've seen. In any case this whole bird thing has been overhyped. There are places where it is not so good to put windmills, and there are techniques that can be used to make them more bird safe. It turns out that newer windmills are generally killing a lot less birds, and the 'this is a disaster' thing was partly based on a couple of extreme cases that were extrapolated to every tower that would ever be built. Its a consideration, but it is nothing like a showstopper.

Fusion will always be radioactive. That is what it is about. Wind will always be expensive because while air flows fast, it is sporadic and light. Wwter is 865 times heavier so you can get a lot of useable horsepower.

Four posts and none of them make much sense. Are you drunk trolling this forum?

As Dubya Bush explained in a State of the Union speech, excess electricity can be stored as hydrogen, wuich can be mixed with natural gas. Because it is excess electrcity, the hydrogen would be chea extra revenue. But Obama does not want to do that because he s catering to foreign despots. Witness the current attacks on our embassies.

Excess methane from when you go to the bathroom could be captured too..

Does that make it a viable power source to power the nation?

Read up on what is required to convert an energy source like solar into hydrogen for storage. I assure you its not cheap and involves a LOT of upfront costs that will most likely never be retrieved. (and of course requires a power source in the first place, so its not like you can say.. move all current subsidy like wind and solar to something like this)

Fusion will always be radioactive. That is what it is about. Wind will always be expensive because while air flows fast, it is sporadic and light. Wwter is 865 times heavier so you can get a lot of useable horsepower.

Fusion, not fission. Yes, there is radioactivity, and it does cause the containment system to become radioactive, but there is no chance for runaway reactions, meltdowns, or catastrophic events that spew radioactivity into the surrounding area.

I went to an enginering school... . Scienc fiction and fantasy do not cu it with me. The nature of both fiseion and fusion is radioactivity. That is what they are based on. Wnd human perfection is a fairy tale. Just ask the folks at Fukushima or Chernobyl or Three Mile Island. Oops" mistakes were made dseves a big, bad raspberry.

What these studies always seem to manage to ignore is the impact from mining/extracting and manufacturing of the parts necessary to build the turbines and infrastructure. It takes a non-trivial amount of rare-earth metals and specialized processes to manufacture these things. Not to mention the equipment necessary to install these towers and infrastructure. This cannot be ignored.

Storing excese electicity as hydrogen is high school chemistry. Light a match and you get a pop. Beyond the problems of fuel cells, hydrogen mixes very well with natural gas. Up to 20% content, chemical properties are similar.

LOL @ turbines at 10km altitude. Just how do they propose getting all that power back down to the ground? They gonna build towers that tall? I'd like to see that. I'm sure the FAA would love it, too. You could go the dirigible route like some are doing now on a small scale, but those are MUCH smaller and only go up a couple hundred feet or so. Good luck dangling 10,000 meters of 350MCM (or larger) DLO cables (anywhere between 8-20 of them) to support each 1MW turbine. You'd need a goddamn Zeppelin to support all that weight, oh, and by the way, they'd have to be the biggest Zeppelins ever built by far. It would only be feasible if you loaded the thing up with batteries that you'd send up to altitude, run for a while to charge, retrieve the unit when fully charged, swap the batteries out with a fresh set, send the balloon back up while plugging your charged-up batteries into the grid.

Sorry but that is exactly the wrong way to engineer the power delivery part of the system. That "problem" was solved earlier in engineering solar power satellites by using MASER links between the satellite and the ground station receivers. Looking at recent advances in materials, that portion of the system has not only become more efficient by far cheaper as well (as has also been seen in recent advances in solar-cell technology.]

Politicians blow gas depending on what they want to do. Then it gets repeated ad nauseum. Doee not make it true. Obama wated wind and solar despite the expense. Republicans are complaining about cronyism for obvious reasons. In the mean time, Obama refuses to export. And so on.

What about the birds!? They forgot the environmental impact of killing off all birds in their model.

Meh, house cats currently kill like 100x more birds than windmills ever dreamed of by most counts I've seen. In any case this whole bird thing has been overhyped. There are places where it is not so good to put windmills, and there are techniques that can be used to make them more bird safe. It turns out that newer windmills are generally killing a lot less birds, and the 'this is a disaster' thing was partly based on a couple of extreme cases that were extrapolated to every tower that would ever be built. Its a consideration, but it is nothing like a showstopper.

I seem to recall that the bird kill issue was largest during the boom times of the 1970s - 1980s in CA when wind farms suffered the following problems:

Sited in migratory bird flyways - Lots of birds in the area, especially less common bird speciess more sensitive to kills like raptors

The turbines spun immensely faster than modern utility turbines - present a greater hazard to birds that fly through the plane of the blades

The use of lattice towers was common - gives birds a place to roost near the blades

Newer wind farms do not suffer these conditions, thus the hazard they present to birds is appreciably diminished. Suspect that plate glass windows, cars, and domestic pets are back to being bigger threats to birds than wind turbines.

What about the birds!? They forgot the environmental impact of killing off all birds in their model.

We'll call it a government subsidy for KFC franchises so they can lower the prices of their "chicken.". Seriously, have you seen their prices lately? WTH happened there? KFC used to be a cheap place to eat! Now it's something like $20 for an 8-piece bucket.

As I have been saying for years we need a nationwide network of wind and solar farms as well as a nation wide network of wireless internet @ minimum of 50Mbs. Oh, and while were at it why not rebuild all of the infrastructure.

That conclusion seems as meaningful as saying that we can supply the entire world's energy demand if we just turn about 6000 kg of mass into pure energy each year. Technically correct, but also pretty worthless.

I know it's not the goal of the study to arrive at how we get there, but I don't think that anyone ever doubted that there's enough energy going on in wind to begin with.

I am pretty sure that if we had taken half the money we put into overthrowing Iraq and Afghanistan and made wind turbines with it instead, we would be well on the way to energy independence, and would have a huge number of new jobs manufacturing, installing and maintaining wind turbines. This would have the side effect of making it easier for us to get out of the middle east.

11 million wind turbines translate to:-11 billion tons of steel: 10x world production rate-130 million tons of aluminium: 3x world production rate-67 million tons of copper: 4,5x world production-800 million tons of plastc: 3,3x world production-40 million tons of electronics-20 billion tons of concrete: 6x world production

In short:Building and maintaining 11 million wind turbines over 20 years (=replacement rate!) would require approximately a half of the entire worlds economic activity directly.

Got a link for these numbers? Having some difficulty imagining that a single 2.5MW wind turbine has 1000 tons of steel, 2000 tons of concrete, 80 tons of plastic, and 4 tons of electronics? About 6 747s worth of steel?

My first thought was also, 'where did these numbers come from?'.

But it does not matter whether these numbers are accurate or not, I don't think that there is any question that this would be an enormous undertaking requiring an enormous amount of material resources.

And last I heard there are some limiting resources such as various rare earth metals.

It would be nice, if wind were evenly distributed. Wind power makes no sense where I live. Average windspeed here is just 3 mph for hundreds of miles around.

Solar doesn't make any more sense here; 250 cloudy days annually.

Thank god for nuclear energy!

First of all the mountains just 100 miles north of Atlanta have winds in the 12-15mph range, and the coast has about the same, and second, solar works even in cloudy weather, just ask the Germans who have the largest solar installations in Europe.

Albeit an interesting article, I think the smaller scale is the bigger answer. Using the newer Geothermal and Fuel Cell technologies are the answer and here's why. If you look at the more compact size of units installed in single family home, you've solved several problems at once. The geothermal units in the http://www.chenahotsprings.com/ project use a standard ac cooling fluids and the generators in their smaller size can work with much smaller temperature differences than traditional geothermal generators. Fuel Cells also have smaller package footprints that can be used for elimination of the power grid. If you are off the grid, then things like grid power outages, such as mother nature, terrorist attacks, or power company failures become an issue of the past. The problem is the Power Industry has spent a great deal of money and time convincing folks otherwise. Americans need to change the way they think, otherwise none of this matters. And PLEASE don't tell me these technologies don't exist. Do your homework! I'm doing mine.

The study does not say what those "substantial climate effects" would be.

More accurately, the article does not. About the study I can say nothing. I've not looked yet but most new studies are behind a paywall, and they stay there for about a year. Abstracts, when available often tell no more than the ars article that referenced them (if the link to it even works).

Quote:

The "substantial climate effects" only occur at the maximum levels of power extraction, as it says in section of text you quoted. This is many times that needed to completely meet global demands.

Reading this it sounds like the effects are binary. Almost no effect until that last turbine is built, then the switch is flipped and the effects become 'substantial' (whatever that means in this context). Now I tend to think that the effects (whatever they may be) will be proportional to the number of turbines built, and increase more or less linearly as more are built. This seems to be the way most everything works. If indeed there is some non-linear relationship here, is there is some non-paywalled material explaining it?

There is no real concept of 'storing power'. That's not how the grid works, either you use it, or auction it off for someone else to use. So what happens at night? Or when there is no wind?

I'm not nitpicking but instead trying to add something to the conversation as I'm somewhat familiar with the power industry. In some geographical locations you can indeed 'store power'. One that readily comes to mind is Raccoon Mountain Pumped Storage Facility in Tennessee. During off peak hours when generation outstrips demand, TVA (Tennessee Valley Authority) pumps large amounts of water to a man made lake on the top of the mountain creating a vast resource of potential energy. During peak hours the pumps (turbines in this case) reverse and act as generators, recapturing the energy kinetically just as a hydroelectric dam does. It's a pretty neat concept and works well.

1) a decent vertical displacement (the larger the head the better) with a large storage area above.2) a significant supply of fresh water to pump.

Most places lack 1) completely, take Florida for example, and most of those that do have 1) don't have 2). And recent droughts show that even if fresh water is abundant today, it may be scarce tomorrow.

-- Two more golden eagles have been found dead at the Los Angeles Department of Water-- and Power wind farm in the Tehachapi Mountains, for a total of eight carcasses of the -- federally protected raptors found at the site.

-- Killing golden eagles is illegal under federal law, but so far, federal authorities have not-- prosecuted any wind farm operators for violations.

The issue I have with this is it is all based on the "standard" model wind turbine. What about using the newer vertical wind turbines which actually gain efficiency from being placed close together and don't appear to have the same detrimental effects on wildlife as the "standard" wind turbines?

Because VAWT's have numerous other practical problems that make them singificantly poorer overall performers. About the only metric they beat HAWT's on is W/acre, which is meaningless since land efficiency is hardly a critical issue for wind farms.

That's not the information I'm seeing in articles and comparisons done in the last year or two. With the advances in materials and design, the VAWTs appear to be at least as efficient if not more efficient converting energy and are more cost efficient than the HAWTs. And because they don't have to "face" the wind and they have a smaller footprint they can be used in more settings than the sprawling wind farms required by the HAWTs. But my main point is: discussing wind power and only focusing on one type of wind generator is like discussing automobile engines and not addressing diesel. You're not getting the whole story.

And oh by the way, for those of you talking about the wildlife, the newer HAWTs are not as detrimental to birds as they used to be. However, the bats have a real problem with the old and new HAWTs and bats eat a lot mosquitos and gnats. For some reason that no one seems to have studied yet, bats don't appear to have as much problem with the VAWTs?

Storing excese electicity as hydrogen is high school chemistry. Light a match and you get a pop. Beyond the problems of fuel cells, hydrogen mixes very well with natural gas. Up to 20% content, chemical properties are similar.

Serious question. Are you drunk? Your various posts have been political and logically problematic. Where does the hydrogen come from? Generally the cheapest way is through natural gas depletion (because electrolysis is too expensive) - so how much of the problem are you solving, after that is the storage is a problem.

Hydrogen doesn't work because you need 10,000 psi to store it, and all the problems and regulations to make 10k compression stupid proof. And you can't put the hydrogen powered vehicle underground parking, 'cause a leak can cause a massive blast that would cause massive damage and loss of life.

The reason I believe that alternatives to gasoline will not pan out is because I look around and see the alternatives and ask myself "If everything ran on "-blank-" and we found out about gasoline" for every alternative the answer is that we would switch to gasoline in a heartbeat, it is just that good - there is so much power stored in such a safe small package. We will have to sort out and mitigate with this whether this is the only fossil fuel to use and how much out of ethanol and bio waste we substitute.

Natural gas use is common so what part of mixing hydrogen with natural gas is difficult to get and how hard is applying a current to water? You are supposed to get oxygen and hydrogen fron H two Oh! $till high school chemistry. Facts remain the same.

There is no real concept of 'storing power'. That's not how the grid works, either you use it, or auction it off for someone else to use. So what happens at night? Or when there is no wind?

I'm not nitpicking but instead trying to add something to the conversation as I'm somewhat familiar with the power industry. In some geographical locations you can indeed 'store power'. One that readily comes to mind is Raccoon Mountain Pumped Storage Facility in Tennessee. During off peak hours when generation outstrips demand, TVA (Tennessee Valley Authority) pumps large amounts of water to a man made lake on the top of the mountain creating a vast resource of potential energy. During peak hours the pumps (turbines in this case) reverse and act as generators, recapturing the energy kinetically just as a hydroelectric dam does. It's a pretty neat concept and works well.

1) a decent vertical displacement (the larger the head the better) with a large storage area above.2) a significant supply of fresh water to pump.

Most places lack 1) completely, take Florida for example, and most of those that do have 1) don't have 2). And recent droughts show that even if fresh water is abundant today, it may be scarce tomorrow.

Natural gas use is common so what part of mixing hydrogen with natural gas is difficult to get and how hard is applying a current to water? You are supposed to get oxygen and hydrogen fron H two Oh! $till high school chemistry. Facts remain the same.

Applying current to water is easy, been done very soon after we had electricity. But how do you get over a total efficiency of 35-40%? The efficiencies of electrolysis of Hydrogen are poor to say the least, so we pull the hydrogens off natural gas. Add this to the trouble with pressure, a far better solution would be to use natural gas strait up, instead of using a round about method to get hydrogen and have all the problems that this causes. But using natural gas...why not just use a longer hydrocarbon and make diesel or gas?

Electrolysis gets multiplied by the efficiencies of the engine of 30-40% some get closer to 50% but most don't, so like 0.35*0.375=13% efficiencies of the electricity pumped into the water gets to moving the car.

Also the volumetric energy is 5 times lower than gasoline...so you need 5x the size of the gas tank to make up the same distance. Weight might be a bit lower because of the small amount higher energy per mass, if we didn't need 5 times tank that had to be reinforced for 10k pressure. Then there is the danger of underground explosions and using things with such high pressures.

The limit on extracting power from wind cannot be determined from an estimate of the energy presently in the wind. That is mostly -stored- energy.

The limit on extracting power from wind is equal to some fraction of the net insolation of the planet. That is, every second there is incoming solar energy, some of which is reflected, some of which warms the surface, and some of which drives air currents (not quite sure whether the latter two overlap ....). It's the total solar energy driving wind, that determines the maximum continuous power extraction from wind.

An analysis presuming that wind is a prime mover, misses physical reality.

The issue I have with this is it is all based on the "standard" model wind turbine. What about using the newer vertical wind turbines which actually gain efficiency from being placed close together and don't appear to have the same detrimental effects on wildlife as the "standard" wind turbines?

Because VAWT's have numerous other practical problems that make them singificantly poorer overall performers. About the only metric they beat HAWT's on is W/acre, which is meaningless since land efficiency is hardly a critical issue for wind farms.

That's not the information I'm seeing in articles and comparisons done in the last year or two. With the advances in materials and design, the VAWTs appear to be at least as efficient if not more efficient converting energy and are more cost efficient than the HAWTs. And because they don't have to "face" the wind and they have a smaller footprint they can be used in more settings than the sprawling wind farms required by the HAWTs. But my main point is: discussing wind power and only focusing on one type of wind generator is like discussing automobile engines and not addressing diesel. You're not getting the whole story.

VAWT's have been the subject of intense study for decades yet haven't scaled up past small experiments for numerous reasons:

Poor self-starting characteristics

Numerous designs typically operate at fantastic speeds - as such can't be placed in locations with high sustained winds and present a safety hazard

They don't scale like HAWT's

MTBF is appreciably worse than HAWT's for most designs

About all I've read in the last year or so about the supposed advance of VAWT's was that Caltech piece where some researcher determined that VAWT's have a better power density per unit of land. Other than that, VAWT developers are always hyping some advance or another that seems not to pan out in the field.

If you've got some links I'd be interested, albeit skeptical.

Quote:

And oh by the way, for those of you talking about the wildlife, the newer HAWTs are not as detrimental to birds as they used to be. However, the bats have a real problem with the old and new HAWTs and bats eat a lot mosquitos and gnats. For some reason that no one seems to have studied yet, bats don't appear to have as much problem with the VAWTs?

Kyle Niemeyer / Kyle is a science writer for Ars Technica. He is a postdoctoral scholar at Oregon State University and has a Ph.D. in mechanical engineering from Case Western Reserve University. Kyle's research focuses on combustion modeling.